The conventionally hydraulically operated dockboard is mounted in a pit in a loading dock and includes a ramp which is hinged at its rear edge to the supporting structure or frame and is adapted to be elevated from a generally horizontal cross traffic position to an upwardly inclined position by a hydraulic cylinder unit that is connected between the supporting structure and the ramp. A lip is hinged to the front edge of the ramp and can be pivoted between a downwardly hanging pendant position and an extended position where it forms an extension to the ramp.
By introducing fluid into the cylinder unit, the ram of the cylinder unit is extended to elevate the ramp. When the ramp has been elevated, the supply of hydraulic fluid to the cylinder is shut off, and the ramp will descend by gravity back toward the horizontal position, and the lip, which is extended at this time, will engage the bed of a truck or carrier located in front of the dock to ridge the gap etween the dock and the carrier bed.
In the past, hydraulic dockboards have been shipped as a complete unit to the site of installation, including the hydraulic system. By shipping the dockboard as a complete unit with the hydraulic system, installation of the dockboard at the dock site is facilitates.
In some cases, a series of dockboards, up to perhaps 15 to 20, may be installed in the loading dock and the practice in the past has been to install each dockboard as a complete unit with an individual hydraulic system.